Lamp retainer structure

ABSTRACT

A bulb retainer device in which a lamp bulb is preloaded, to facilitate bulb mounting and replacement in a lamp-housing structure adapted to support either a single bulb or a bank of two or more bulbs. The retainer is particularly useful in the mounting and replacement of high intensity &#39;&#39;&#39;&#39;PAR&#39;&#39;&#39;&#39;-type bulbs which become too hot for direct handling and require frequent replacement. The retainer cooperates in a new way for the removable mounting of bulbs having ferrule-type terminals in lamp structures having cooperating spring contacts, the biasing force of the contacts providing spring-seated mounting of the bulb.

United States Patent 2/1966 McDonald 240/ l .2 3,263,204 7/1966Fitzgerald....... 339/154 3,309,512 3/1967 Conley et al.... 240/133,375,367 3/1968 Woodcock 240/521 3,515,864 6/1970 Levy et al. 240/442Primary Examiner-Richard C. Queisser Assistant Examiner-John WhalenAttorney-Fulwider Patton Rieber Lee & Utecht ABSTRACT: A bulb retainerdevice in which a lamp bulb is preloaded, to facilitate bulb mounting;and replacement in a lamp-housing structure adapted to support either asingle bulb or a bank of two or more bulbs. The retainer is particularlyuseful in the mounting and replacement of high intensity PAR type bulbswhich become too hot for direct handling and require frequentreplacement, The retainer cooperates in a new way for the removablemounting of bulbs having ferrule-type terminals in lamp structureshaving cooperating spring contacts, the biasing force of the contactsproviding spring-seated mounting of the bulb.

mamtum 4m SHEET 1 [1F 3 LAMP RETAINER STRUCTURE BACKGROUND OF THEINVENTION The present invention relates generally to the mounting ofhigh-intensity bulbs in the housing structures of lamps employedprincipally for photographic-type illumination, as for example toilluminate either indoor or outdoor scenes for television, motionpicture or still picture photographic purposes.

Historically, lamp bulbs have been directly inserted into socketstructures in the lamp housing, even the high-intensity type of bulbscommonly employed in the television and motion picture industries. Thispresents a difficult handling problem because such high-intensity bulbsgenerally have only a short operational life, and therefore must befrequently replaced. However, such bulbs are generally too hot to handlewhen they first go out, thus resulting in expensive down time of theequipment while waiting for the bulb to become sufficiently cool to behandled.

This problem is compounded where the bulbs are of the PAR high-intensitytype resembling a seal-beam" headlamp wherein glass reflector and lenscomponents come together at a sealed peripheral flange that is grippedin the mounting. Bulbs of this type having screw-type terminals on theback have typically been mounted by tilting the bulb and sliding oneedge thereof into a channellike retainer, and then straightening thebulb into its operative position and moving a spring retainer deviceover the opposite edge of the bulb. On the other hand, bulbs of thisgeneral type which were equipped with ferrule-type terminals on the backthereof adapted to mate with spring contacts in the housing, weretypically pushed into place against the spring biasing of the contacts,and a retainer rim placed over the periphery of the face of the bulb andclamped down against the front of the lamp structure by engagement ofcaptive thumb nuts on the retainer rim with forwardly projectingthreaded studs on the front of the housmg. Both of these types ofmountings for PAR-type high-intensity bulbs have come into widespreadcommercial use because of the advantages of this type of bulb, but themounting and replacement of bulbs in each type involves a number ofserious problems which are solved by the present invention. Thus, withboth of these conventional mountings, when a bulb went out during theshooting of a scene, it was too hot to immediately handle, and thereforegenerally involved costly down time of the equipment. Also, loading andunloading was generally awkward and time consuming, even after the bulbhad cooled. Thus, with the screw terminal type bulb, it was necessary tofirst remove the screw terminals from the bulb, then push the springretainer back off of one edge of the bulb, slide the opposite edge ofthe bulb out from the channel member, and then the reverse of thisprocedure was required for the installation of the new bulb. With thespring contact, ferrule terminal arrangement, it was generally awkwardto accomplish proper centering and contact mating since theterminals andcontacts were completely obscured by the main part of the bulb once thebulb was inserted into its socket, and it was also generally awkward tobalance the bulb in its aligned position with the contacts mated and atthe same time place the retainer rim down against the periphery of thebulb and engage and tighten the thumb nuts onto the housing studs. Inpractice, with this type of mounting wherein a retainer rim was clampeddown against the periphery of the bulb by thumb nuts, it was foundnecessary to employ a high-temperature silicone rubber-type of gasket asa pad to prevent damage to the glass bulb from the tight metal clampingthereof and from physical shocks to which the lamp might be subjected.

SUMMARY OF THE INVENTION In view of these and other problems in the art,it is an object of the present invention to provide bulb retainerstructure having means therein for releasably securing a lamp bulb tothe retainer structure, and also having means thereon for releasablyattaching the retainer structure and captive bulb to a lamp housingstructure, whereby one or more of such retainer structures may bepreloaded with bulbs so that the bulbs can be mounted in the lamphousing structure without direct handling of the bulb, making mountingand replacement of bulbs more rapid and convenient, and avoiding thenecessity of direct handling of hot bulbs when the rapid replacement ofa burned out bulb is necessary to keep the lamp equipment in operation.

Another object of the invention is to provide lamp bulb retainerstructure of the character described which is adapted to receive a lampbulb of the type that is peripherally supported, as for example aPAR-type of bulb, the retainer being conveniently releasably attachableto a lamp housing to form a face portion of the housing which in effectframes the bulb, by engaging thumb nuts on the retainer with studsprojecting forwardly from the housing, thereby permitting the mountingand replacement of bulbs in housing without directly handling the bulbs.

A further object of the invention is to provide a novel bulb retainerstructure of the character described wherein the bulb is loosely engagedin the retainer without requiring tight metal-to-glass clamping andwithout requiring the use of rubber gaskets or the like to protect thebulb against damage from tight clamping between metal parts, theretainer cooperating with spring contacts in the housing which forwardlybias the bulb in the retainer to provide positive seating for the bulbin the retainer.

A still further object of the invention is to provide bulb retainerstructure of the character described having releasable bulb retainermeans therein which is compact, allowing a bulb retainer of minimumexternal dimensions, is simple and easy to operate, yet is positive andsecure in its retaining function.

Further objects and advantages of this invention will appear during thecourse of the following part of the specification, wherein the detailsof construction and mode of operation of a preferred embodiment aredescribed with reference to the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of asix-bulb lamp embodying six of the retainer units of the presentinvention, with one retainer and associated bulb illustrated in explodedrelationship with respect to the lamp.

FIG. 2 is an exploded perspective view of a retainer unit according tothe invention and a PAR-type bulb axially aligned with the retainer unitpreparatory to engagement of the bulb in the retainer unit.

FIG. 3 is an enlarged, fragmentary front elevational view showing partof the lamp illustrated in FIG. 1, with portions broken away toillustrate internal details of construction.

FIG. 4 is a vertical section taken on the line 4-4 in FIG. 3.

FIG. 5 is a horizontal section taken on the line 5-5 in FIG. 3.

FIG. 6 is a rear elevation, with portions broken away, of the retainerunit with a bulb mounted therein, independent of the lamp housingstructure.

FIG. 7 is a vertical section, with a portion broken away, taken on theline 7-7 in FIG. 6.

FIG. 8 is a horizontal section taken on the line 8-8 in FIG. 6.

FIG. 9 is a fragmentary horizontal section taken on the line 9--9 inFIG. 6.

DETAILED DESCRIPTION Referring to the drawings, and at first inparticular to FIGS. 1 and 2 thereof, a lamp 10 is shown wherein sixretainer units according to the invention are employed for the mountingof six respective bulbs of the PAR"-type,. in three vertical banks oftwo bulbs each arranged side by side, so that the lamp I0 is a generallyflat, rectangular structure having the six bulbs directed generally fromone side thereof.

The lamp includes a frame structure 12 in the general form of aninverted U-shaped strap which is pivotally mounted in a yoke 14 forminga portion of a support stand, so as to pivot or tilt about a generallyhorizontal axis 16. A rectangular control box 18 is mounted on the lowerportion of frame structure l2 and contains conventional cableterminations, electrical junctions and switches for controlling the lamp10. The control switches may be mounted on the rear panel of control box18, and are not shown in the drawings. Horizontal bars 20 and 22 onframe 12 and control box 20, respectively, provide handle means formanipulation of the lamp l0, and convenient means for mounting filterstructures or the like in front of the lamp 10.

The lamp 10 illustrated in FIG. 1 includes three discrete lamp housings24, 26 and 28 which are generally elongated, vertically arranged housingunits each being adapted to receive two retainer units 30 according tothe invention in vertically stacked relationship thereon, with tworespective bulbs 32 preloaded and captive in the retainer units 30.

Each of the lamp housings 24, 26 and 28 comprises a shell 34 having arearward portion 36 of perforated sheet metal which is generally in theshape of a frustum in horizontal section, with sides 38 extendingforwardly therefrom that terminate in respective inturned forwardflanges or lips 40. Each shell 34 also includes a generally horizontaltop wall 42 and bottom wall 44, with an angle brace 46 providingreinforcement to the top wall 42. The housings 24 and 28 at the sides ofthe lamp 10 are mounted for pivoting about vertical axes between the topof frame structure 12 and the box 18. Handles 48 are connected to eachthese pivoted housings 24 and 28 on the respective pivot axes forconvenient pivotal movement of the housings 24 and 28. The centerhousing 26 is preferably fixedly mounted between the frame 12 and box18, as for example by means of a bolt 50 to provide connection ofhousing 26 to frame 12, and a tubular connection between the bottom ofhousing 26 and the box 18 similar to the tubular pivot connection 52shown in FIG. 1 which connects the bottom wall 44 of housing 28 with thecontrol box 18, and provides a conduit for the electrical powerconductor means 54 to pass from the control box 18 into the lamp housing28.

As best seen in FIGS. 1, 3, 4 and 5, a pair of flat bars or straps 56extends transversely across each of the lamp housings 24, 26 and 28,each of these bars or straps 56 being secured at its opposite ends tothe rearward surfaces of the opposed flanges 40, with one bar or strap56 extending across each housing 24, 26 and 28 adjacent the top thereof,and the other located just below the centerline between the top andbottom of each housing 24, 26 and 28. One end of each of the bars orstraps 56 is connected to its respective flange of the housing by meansof a bolt 58, while the other end is connected to its respective flange40 by the base structure of a threaded stud 60 which projects forwardlyfrom the respective housing 24, 26 or 28. Thus, one such threaded stud60 projects forwardly from one flange 40 near the top thereof, andanother such threaded stud 60 projects forwardly from the same flange 40just below the vertical center of that flange 40. Similar threaded studs62 extend forwardly from the other flange 40 just above the verticalcenterline and adjacent the bottom thereof. In this manner, the upperstuds 60 and 62 of each housing 24, 26 and 28 provide attachment meansfor an upper retainer unit 30, and the lower studs 60 and 62 of eachhousing 24, 26 and 28 provide attachment means for a lower retainer unit30. Each retainer unit 30 is preferably substantially square, and sinceit supports a substantially round bulb 32 therein there is substantialroom on one pair of opposite corners thereof for the provision ofcaptive thumb nuts adapted to engage a complementary pair of studs 60and 62.

The two flat bars or straps 56 in each housing 24, 26 and 28 eachprovide support means for a spring contact assembly generally designated64, which includes an insulator body 66 extending rearwardly from therespective bar or strap 56 and connected thereto by means of bolts 68. Apair of electrical contacts 70 is supported on respective leaf springmembers 72 that are secured to each insulator body 66, and anirisulation sheet 74 is supported on each insulator body 66 and extendsunderneath the respective contacts 70 to isolate the contacts 70 fromthe perforated rearward portion 36 of the respective housing.

The combination of retainer unit 30 and captive bulb 32 is bestillustrated in FIGS. 2, and 6 to 9, which illustrate these componentsseparated from the remainder of the lamp. The body of the retainer 30may be drawn or otherwise formed from sheet metal, and includes a flat,square front wall or panel 76, the central part of which is cut away toprovide a large circular aperture 78. Shell sidewalls and 82 extendrearwardly from the side edges of the front wall or panel 76, while topand bottom walls 84 and 86 extend rearwardly from the respective top andbottom edges of the front wall or panel 76 the same distance as thesidewalls 80 and 82.

The PAR"-type bulb 32 is a circular glass envelope having convex forwardlens and rearward body portions which come together at a stepped annularrim comprising a flange portion 88 and a forward annular edge 90 ofsmaller diameter than the flange 88 which defines the periphery of thelens. A positioning lug 92 projects radially outwardly from the rearwardbody portion of the bulb for rotational orientation of the bulb in theretainer 30. A pair of spaced, ferrule-type terminals 94 projectsrearwardly from the body of bulb 32, the terminals 94 being spaced apartsubstantially the same amount as the contacts 70 of the spring contactassembly 64 so as to register with a pair of such contacts 70 when theretainer unit 30 and captive bulb 32 are operatively engaged with eitherthe upper or the lower half of one of the lamp housings 24, 26, or 28.

A fixed bulb retainer bracket 96 in the form of an elongated anglemember has a sidewall portion 98 thereof which is secured along theinwardly facing surface of the retainer sidewall 80, with a flangeportion 100 thereof projecting laterally inwardly generally parallel tothe front wall 76 of the retainer but spaced rearwardly therefrom. Thisflange portion 100 of the bracket 96 has a notch or recess 102 thereinthat is adapted to receive the positioning lug 92.

A pivoted retainer bracket 104, also in the form of an elongated anglemember, has a sidewall portion 106 thereof which is pivoted proximateone end flush against the inwardly facing surface of the retainersidewall 82 as by means of a pivot pin 110in the form of a rivet. Theretainer bracket 104 also includes a flange portion 108 which projectsinwardly from the sidewall 82 generally parallel to the front wall 76and spaced rearwardly from the latter. The flange portion 108 of thepivoted retainer bracket 104 is provided with a curved gripping edge 112proximate its free end for comfortable engagement of the free end of theflange portion 108 with a finger to swing the pivoted retainer bracket104 between its closed position as shown in solid lines in FIGS. 6 to 9,and an open position such as illustrated in FIG. 2.

The pivoted retainer bracket 104 is releasably secured in its saidclosed position by means of a retainer spring 104 mounted on theretainer body adjacent the free end of the pivoted retainer bracket 104when the latter is in its said closed position, and disposed immediatelyadjacent to the retainer sidewall 82. The retainer spring 114 ispreferably a leaf-type spring having a base tab 116 fixedly securedagainst the rearwardly facing surface of the front wall 76 of theretainer body, as by means of rivet 118, the spring having a generallyrearwardly extending U-shaped operative portion including a leg 120which extends rearwardly from the base tab 1 16, a curved rearward end122 and a forwardly extending leg 124 which is immediately adjacent tothe sidewall 82 of the retainer sidewall and is preferably prestressedso as .to press against the wall 82, so that when the pivoted retainerbracket l04'is moved to its closed position, the sidewall portion 106 ofthe latter is tightly compressed between the spring leg 124 and theinwardly facing surface of the sidewall 82 of the retainer body as bestillustrated in FIGS. 6 and 9. The curvature of rearward end 122 of theretainer spring 114 provides a suitable lead-in for easy entry of theforward edge of wall 106 of the pivoted retainer bracket'104 between thespring and the sidewall 82 of the retainer body.

Two captive thumb nuts 126 are mounted in the front wall 76 of theretainer unit adjacent opposite corners thereof, hav- =ing knurledgripping portions which project forwardly from the front wall 76, andbeing adapted for threaded engagement with a pair of the studs 60 and 62which project forwardly from one of the lamp housings 24, 26 or 28. Itwill be noted from FIG. 6 that the bulb retainer brackets 96 and 104 areoffset so as to provide ample clearance for the thumb nuts 126 and forengagement of the threaded studs 60 and 62 therewith. Thus, as viewed inFIG. 6, the fixed retainer bracket 96 is positioned toward the lowerportion of the sidewall 80, leaving substantial clearance above theupper end of the retainer bracket 96 for the stud 60 and the respectivethumb nut 126 engageable therewith. Similarly, the pivoted retainerbracket 104 is offset toward the upper end of sidewall 82, being pivoteda substantial distance above the bottom wall 86, to provide ampleclearance for the threaded stud 62 and its respective thumb nut 126. Byoffsetting the pivoted retainer bracket 104 in this direction, insteadof in the op posite direction, the center of retaining engagement of thepivoted bracket 104 with the periphery of bulb 32 is substantiallycloser to the pivot 110 than it is to the free end of pivoted bracket104 which is gripped in the retainer spring 114. In this manner, thepivoted retainer bracket 104 functions as a lever which increases themechanical advantage of the retention force of retainer spring 114 byhaving a relatively short distance from the fulcrum 110 to the center ofengagement with the periphery of bulb 32 proximate the section line 8-8in FIG. 6, and a relatively long distance between the fulcrum 110 andthe free end portion of bracket 104 which is gripped by the retainerspring 114.

In order to load an empty retainer unit 30 with a bulb 32 preparatory tothe mounting of the combination of retainer and bulb in the lamp, thepivoted retainer bracket 104 is swung rearwardly to a fully openedposition generally as illustrated in FIG. 2, and the bulb 32 is arrangedgenerally behind the retainer 30 as illustrated in FIG. 2. The rim ofbulb 32 proximate positioning lug 92 is then engaged under the flangeportion 100 of the fixed retainer bracket 96, with the positioning lug92 disposed in notch or recess 102 so as to orient the bulb with itsferrule terminals 94 positioned for engagement with a respective pair ofthe contacts 70. Then the pivoted retainer bracket 104 is simply swungforwardly to its closed position with its free end gripped by theretainer spring 114, so as to engage the rim of bulb 32 at a pointthereon diametrically opposed from the positioning lug 92. The circularaperture 78 in the front wall 76 of the retainer body is slightly largerin diameter than the step 90 at the forward annular edge of the bulblens, so that the latter seats forwardly into the circular aperture 78as best illustrated in FIG. 8. The bulb 32 is by this means quickly andeasily securely retained and rendered captive in the retainer unit 30 sothat further handling of the bulb is unnecessary, and the bulb can thenbe operatively positioned or removed from the lamp 110 as desired solelyby manipulation of the retainer 30.

Mounting of the bulb-loaded retainer unit 30 in one of the housingportions of the lamp I0 is conveniently effected simply by arranging theloaded retainer unit in front of an open housing section with theretainer thumb nuts I26 axially aligned with the respective threadedstuds 60 and 62 on the housing, as illustrated in FIG. 1, and thenmoving the retainer unit rearwardly until the studs are engaged in thethumb nuts I26 and then taking the thumb nuts down onto the studs untilthe retainer unit 30 is substantially tight against the front of thelamp housing. As the retainer is thus being tightened into place, thetwo ferrule terminals 94 on the bulb 32 are brought into engagement withthe contacts 70 and move the contacts 70 rearwardly against the biasingforce of their respective leaf springs 72, thereby effectingspring-loaded contacting engagement between the contacts 70 and theferrule terminals 94, and additionally biasing the bulb 32 forwardly inthe retainer unit 30 so that the bulb becomes securely fixed in aforward most, seated position in the retainer unit 30 and will notrattle under ordinary usage of the lamp. The fit of the bulb 32 in theretainer unit 30 prior to such attachment of the retainer unit 30 with alamp housing is preferably somewhat loose so as to rely upon the biasingforce of the spring contacts to hold the bulb 32 in its fully seatedposition in the overall lamp structure I0. By this means economy iseffected by avoiding the necessity of close-tolerance fitting betweenthe bulb and retainer, and tight metal-to-metal gripping of the bulb isavoided, thus substantially lessening the likelihood of damage ,to thebulb. Additionally, the need for rubber gaskets or pads to protect thebulb against glass-to-metal contact is avoided since the amount ofclamping force of the bulb against the retainer is limited by thestrength of the contact springs 72, which is a fully controllablefactor.

Preferably, several retainer units 30 will be preloaded with respectivebulbs 32 so that if a bulb that is in the lamp It) goes out duringoperation of the lamp, it can be quickly and easily replaced withoutdirect handling of the hot burned-out bulb by simply unscrewing the twothumb nuts 126 on the respective retainer unit 30 and setting thatretainer unit and bulb combination aside until it cools off, andreplacing the removed combination by a preloaded retainer unit and bulbcombination.

By having only two of the captive thumb nuts 126 and respective studs 60and 62 at opposite corners of the retainer and housing section to whichthe retainer is applied, regardless of which of the two positions inwhich the retainer can be oriented for engagement of the thumb nuts 126with the respective studs 60 and 62, the ferrule terminals 94 on thebulb will be generally horizontally aligned and will be axially alignedwith the pair of contacts 70. Thus, while the retainer unit 30 has beendescribed hereinabove as having top and bottom walls 84 and 86, inpractice either one of these walls can be at the top when the loadedretainer unit is operatively engaged with the lamp.

While the instant invention has been shown and described herein in whatis conceived to be the most practical and preferred embodiment, it isrecognized that departures may be made therefrom within the scope of theinvention, which is therefore not to be limited to the details disclosedherein, but is to be accorded the full scope of the appended claims.

I claim:

1. In a lamp having a forwardly opening housing with elec trical contactmeans therein, and a bulb having a body with rearwardly exposed terminalmeans and a peripheral rim, the combination with said lamp of a bulbretainer comprising a forward Wall with an aperture therethrough, a pairof flanges on said retainer located generally on opposite sides of saidaperture spaced rearwardly from said forward wall and having normalretaining positions wherein they extend inwardly toward each other inopposed relationship, the bulb normally being retained in said retainerby engagement of said peripheral rim between said forward wall and saidflanges, one of said flanges being movable from its said retainingposition to an open position clear of the bulb rim to permit removal andreplacement of the bulb, and coupling means releasably engageablebetween the retainer and housing for removably mounting the retainer onthe front of the housing with said ter minal and contact meansoperatively engaged, said retainer including peripheral wall meansextending rearwardly from the periphery of said forward wall, saidperipheral wall means generally enclosing the bulb rim and having a pairof generally parallel, opposite sidewall portions, said flangesprojecting in wardly from the respective said sidewall portions, saidmovable flange being one side of an elongated angle member, the otherside of which is disposed generally in side-by-side relationship withthe respective sidewall portion and pivoted adjacent one end thereof tosaid respective sidewall portion.

2. The combination as defined in claim 1, which includes spring retainermeans on the bulb retainer frictionally engage able with said other sideof said elongated angle member proxinun-r 11L imate the free end thereofto releasably secure said movable flange in its said retaining position.

373 5 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,633,024 Dated Januarv 4 1972 Inventor(s) MAXEY A. HANKINS It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Column 4, line 68, after "retainer" delete "sidewall" and inserttherefor -body,..

Signed and sealed this lLpth day of November 1972.

(SEAL) Attest:

EDWAR MJL T IER R. Y 1 A ROBERT GOTTSCHALK Attestlng offlcerCommissioner of Patents

1. In a lamp having a forwardly opening housing with electrical contactmeans therein, and a bulb having a body with rearwardly exposed terminalmeans and a peripheral rim, the combination with said lamp of a bulbretainer comprising a forward wall with an aperture therethrough, a pairof flanges on said retainer located generally on opposite sides of saidaperture spaced rearwardly from said forward wall and having normalretaining positions wherein they extend inwardly toward each other inopposed relationship, the bulb normally being retained in said retainerby engagement of said peripheral rim between said forward wall and saidflanges, one of said flanges being movable from its said retainingposition to an open position clear of the bulb rim to permit removal andreplacement of the bulb, and coupling means releasably engageablebetween the retainer and housing for removably mounting the retainer onthe front of the housing with said terminal and contact meansoperatively engaged, said retainer including peripheral wall meansextending rearwardly from the periphery of said forward wall, saidperipheral wall means generally enclosing the bulb rim and having a pairof generally parallel, opposite sidewall portions, said flangesprojecting inwardly from the respective said sidewall portions, saidmovable flange being one side of an elongated angle member, the otherside of which is disposed generally in side-by-side relationship withthe respective sidewall portion and pivoted adjacent one end thereof tosaid respective sidewall portion.
 2. The combination as defined in claim1, which includes spring retainer means on the bulb retainerfrictionally engageable with said other side of said elongated anglemember proximate the free end thereof to releasably secure said movableflange in its said retaining position.